FIG. 1 shows an exploded view of a prior art disk drive comprising a disk 2 rotated by a spindle motor 4, and a head 6 coupled to a distal end of an actuator arm 8 which is rotated about a pivot 10 by a voice coil motor (VCM) in order to actuate the head 6 over the disk 2. The disk 2, spindle motor 4, head 6, actuator arm 8, and VCM are enclosed in a head disk assembly (HDA) comprising a base 9 and a cover 11. The VCM comprises a voice coil 12 coupled to the base of the actuator arm 8 and one or more permanent magnets attached to a yoke 14. When the voice coil 12 is energized with current, the resulting magnetic flux interacts with the magnetic flux of the permanent magnets to generate a torque that rotates the actuator arm 8 about the pivot 10. A tang 16 attached to the actuator arm 8 interacts with a crash stop 18 to limit the stroke of the actuator arm 8, and also provides a latching mechanism (e.g., using a magnet) to maintain the actuator arm 8 in a latched position while the disk drive is powered down. Alternatively, the actuator arm 8 may be parked on a ramp located at the outer periphery of the disk 2 when the disk drive is powered down.
During manufacturing, the HDA is passed through an assembly line of “stations” each responsible for installing particular components using appropriate installation tools. For example, one manufacturing station may install the spindle motor 4 into the base 9, another station may clamp the disk 2 to the spindle motor 4, another station may install the head stack assembly (actuator arm 8, head 6, voice coil 12), another station may install the crash stop 18, another station may install the yoke 14 of the VCM, and another station may install the HDA cover 11. Although manufacturing the HDA typically occurs in a clean room environment, there is still a risk that particles will contaminate the surface of the disk 2 as the HDA passes through the various manufacturing stations.
There is, therefore, a need to protect against particles contaminating the disk surfaces while manufacturing the HDA of a disk drive.